I do a very similar (hilly) daily commute but don't have to face snow very often, just a lot of rain/gales/sticky muddy lanes in the winter - the bike I reach for most often is a rugged 90's steel framed tourer with a rear rack and a set of ortleib panniers. The geometry of a tourer is usually fairly relaxed and stable and they can take reasonably wide tires if needed (similar geometry to a Rivendell style frame I think). I run Marathon Plus to avoid as many punctures as possible and honestly they roll just fine for this kind of distance. I like a square taper BB because they're easy to maintain and adjust and there's plenty of choices of economic cranksets if you want to try some different ratios to suit your terrain.
You'll probably get a ton of variety in suggestions because we all like different things - my priority for my commuter is a durable, serviceable machine that can carry some luggage but is still fun to ride.